>No, but the likelihood of the argument having any value is greatly reduced if the person themself doesn't believe in it enough to actually follow the argument.

Total nonsense. So a drunk who's destroyed their own life telling some teenagers about the dangers of alcohol greatly reduces the likelihood of his argument being valid since he still drinks? Ridiculous. Crying "hypocrit" is just ad hominem. Nothing more noble than that.

Oh, nonsense. It's entirely about the argument's validity, and this bit about the source's trustworthiness is a red herring. Is this "source" claiming to reveal secret information about Google's being a big ad business we can't verify for ourselves and that would change our minds if we decide that he can be trusted?

Nothing of the sort. He's expressing an opinion about things that nobody disputes. Calling him a hypocrite means you don't like his opinion and think that calling him names is a good way to weaken his argument. Of course it's meaningless and defending such silliness on the grounds that this is all about the credibility of an information source is beyond silly.